This invention relates to a valve assembly for a fuel tank. More particularly, this invention relates to a vehicle fuel tank filler neck and a valve for admitting a tube or fuel into the fuel tank through the filler neck.
When repairing or maintaining a vehicle, a mechanic may need to remove liquid fuel from the vehicle fuel tank before beginning maintenance. To accomplish removal of the fuel, the mechanic may insert a tube or hose through a filler neck into the fuel tank and then siphon or pump the fuel from the fuel tank. This procedure is relatively simple if the length of the filler neck is unobstructed from the filler neck inlet to the fuel tank. Other fuel tanks (not in vehicles) may also be emptied in a similar way.
In many modern vehicles, filler necks are equipped with obstructions such as fuel splash or overfill prevention mechanisms to prevent the unrestricted escape of fuel and fuel vapor from the fuel tank through the filler neck into the atmosphere. Moreover, a filler neck may not be optimally oriented on the fuel tank for an inserted siphon tube to penetrate into the liquid fuel.
The present invention provides a valve assembly for a fuel tank for admitting a tube or fuel into the fuel tank through a filler neck in which the component parts of the valve assembly are simple and economical to manufacture, assemble, and use. Other advantages of the invention will be apparent from the following description and the attached drawings or can be learned through practice of the invention.
According to an aspect of the invention, a valve assembly for admitting a tube or fuel into a vehicle fuel tank has a fixed housing with an inlet, an outlet and a middle section located between the inlet and outlet. The housing has an inner surface with an opening and at least one projection located between the inlet and the outlet. Illustratively, the fixed housing may be connected in the fuel tank such that the outlet extends in a direction towards a bottom of the tank.
The projection in the housing depends or extends from the inner surface and is configured to deflect the tube toward and through the opening. The valve assembly may have at least one other projection, which is spaced axially apart from the first mentioned projection such that the two projections cooperate to deflect the tube toward and through the opening.
A plurality of projections can be provided. Any or all of the projections may extend substantially perpendicular from the inner surface. Moreover, at least two projections may extend parallel to each other at a common axial position in the housing in spaced apart relationship from each other.
In this aspect of the invention, the projections present a surface area that is substantially less than an open area adjacent the surface area to permit substantially unimpeded fuel passage. To facilitate better directional control of the hose, the surface area may slant from the inner surface in the direction of the outlet.
The valve assembly may include a piston element, which is slidably mounted to the housing and urged in a first direction to close the outlet and the opening. The piston element is movable in a second direction opposite the first direction by the tube or fuel. Preferably, the piston element has a substantially flat surface element and a retaining end. The flat surface element is located in the direction of the projection and spaced axially apart from the retaining end, which is located in the direction of the fuel tank. The flat surface element may be on an elevated element.
Optionally, the valve assembly may have a spring element for urging the piston element in the first direction to close the outlet and the opening. The spring element can have a spring constant such that the tube and/or fuel can move the piston element in the second direction upon insertion of the tube and/or fuel into the housing.
A sealing element may be attached circumferentially about the piston element. Additionally, an annular stop portion may extend from the inner surface for sealingly engaging the sealing element of the piston element to provide additional liquid fuel splash control.
According to another aspect of the invention, a fuel valve assembly for a fuel tank filler neck is disclosed. The fuel valve assembly includes a frame fixed in the filler neck. The frame defines a central axis and has an inlet, an outlet, a middle channel having an inner surface therein, and at least one axially extending opening therein spaced apart from the outlet for passage of a hose. The inlet is in selective communication to an atmosphere external to the fuel tank and the outlet is in selective communication with the fuel tank. The inlet and outlet are spaced apart from each other to define the middle channel.
The fuel valve assembly also has a finger element having a proximal end and a distal end. The proximal end is attached to the inner surface, and the distal end projects radially inward, substantially perpendicular to the central axis. The distal end may be tapered, and a circumferential shoulder element may be disposed about the inner surface near the at least one axially extending opening.
The fuel valve assembly also includes a piston arrangement having a piston element with an elevated surface and a guide end. A seal is spaced apart from the guide end proximate the elevated surface, and a compression piece or spring is attached to the piston element configured to urge the seal against the shoulder element. Preferably, the elevated surface has a substantially flat center and defines a curved, circumferential outer edge. A circumference of the seal is greater than the elevated surface outer edge such that the piston element is disposed concentrically to the circumference of the seal, the piston element and the finger element cooperating to protect the seal from the hose.
The piston element is further configured to resistively open the at least one axially extending opening for passage of the hose. The guide end is configured to retain the piston element in the frame in substantial axial alignment with the central axis.
In a further aspect of the invention, the at least one axially extending opening is spaced apart from the finger element such that the finger element deflects the hose through the at least one axially extending opening. Additionally, a plurality of finger elements, each having a radially slanted surface area, may be provided. A passage area is disposed about the plurality of finger elements. The passage area is substantially greater than the radially slanted surface area.
According to another aspect of the invention, a check valve assembly for a vehicle fuel tank filler neck is disclosed. The check valve assembly includes a support frame coupled to the filler neck, the support frame having a centerline and an inlet in communication with the filler neck and defining an inner surface area therein, an opening therethrough, and an outlet in communication with a fuel tank with the opening spaced axially apart from the outlet. The inlet is configured for receiving fuel and a siphon tube.
The check valve assembly is configured to deflect the tube through the opening. A protrusion or other provision is disposed on the inner surface area and may have contoured surfaces for deflecting the tube. In one aspect, the protrusion or other provision includes at least two projecting parts each having a distal end, at least one of the projecting parts disposed on the inner surface area at a point spaced axially and/or laterally apart from at least another of the projecting parts, the at least two projecting parts disposed relative to each other such that the tube must pass substantially along the centerline of the frame. Alternatively, the protrusion or other provision may be enlarged projecting parts having holes or an arrangement of openings configured to permit substantially unimpeded flow of liquid fuel past and through the means for deflecting. The holes have sufficiently small diameters, widths, or lengths so as to not ensnare the siphon tube.
A blocking element is movably disposed within the support frame in the vicinity of the opening and the outlet for sealing the opening and the outlet. The blocking element cooperates with the deflecting provision, which may have contoured surfaces, such that the tube passes through the opening when extended into and through the frame. Moreover, an abutment element may be circumferentially disposed about the blocking element and carry a seal for engaging the support frame. The abutment element can be configured to releasably urge the blocking element in a direction towards the filler neck.